The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. The previous two releases were characterised by several large gazetted areas in underexplored regions, a trend that is maintained this year with several frontier areas in excess of 100 graticular blocks on offer. The uptake of new exploration permits in the Bight Basin, the offshore North Perth Basin and the Roebuck Basin indicates a continuing strong industry interest in offshore frontier exploration.

The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. These areas are located across various offshore hydrocarbon provinces ranging from mature basins with ongoing oil and gas production, to exploration frontiers. A total of 23 areas are released for work-program bidding and six areas for cash bidding. The two work-program bidding rounds will remain open until 29 October 2015 and 21 April 2016 respectively, while cash bid submissions will close on 4 February 2016. The 2015 Release Areas are located in thirteen distinct regional geological provinces across eight basins and all were supported by industry nominations. Six areas are located in the Bonaparte Basin, two of which are cash bid areas over the Turtle/Barnett oil accumulations. The Browse Basin is represented by three areas in the Caswell Sub-basin and one area on the Yampi Shelf. In support of recent exploration activities and success, one large area has been gazetted in the central Roebuck Basin. The Northern Carnarvon Basin offers eleven areas on the Exmouth Plateau and in the Dampier Sub-basin including four for cash bidding. This year, the usual predominance of North West Shelf Release Areas is counterbalanced by seven large areas in the Bight, Otway, Sorell and Gippsland basins. This includes one area in the Ceduna Sub-basin, three areas in the deep water Otway Basin, one area in the northern Sorell Basin and two areas in the south-eastern Gippsland Basin. Receiving nominations for these areas highlights the industry's interest in evaluating the hydrocarbon potential of Australia's underexplored southern margin. Geoscience Australia continues to support industry activities by acquiring, interpreting and integrating pre-competitive datasets that are made freely available as part of the agency's regional petroleum geological studies.

No abstract available

Updated USB drive containing GA-reports, maps in digital format to be handed out as promotioanl material at APPEA conference

In 2021, a total of 21 areas were released for offshore petroleum exploration. They are located in the Bonaparte Basin, Browse Basin, Northern Carnarvon Basin, Otway Basin, Sorell Basin and Gippsland Basin. Despite COVID-19 negatively impacting the industry, participation in the acreage release nomination process was again robust, however, as has been the case in recent years, industry interest is focussed on those areas that are close to existing discoveries and related infrastructure. In tune with the Australian government’s resource development strategy, the areas being offered for exploration are likely to supply extra volumes of natural gas, both for export to SE Asian markets and domestically to meet the forecasted shortage in eastern Australia. According to the 2019 implementation of a modified release process, only one period for work program bidding has been scheduled. The closing date for all submissions is Thursday, 3 March 2022. Geoscience Australia continues to support industry activities by acquiring, interpreting and integrating pre-competitive datasets that are made freely available in the context of the agency’s regional petroleum geological studies. As part of a multidisciplinary study, new data, including regional seismic and petroleum systems modelling for the Otway Basin is now available. Also, a stratigraphic/sedimentological review of the upper Permian to Early Triassic succession in the southern Bonaparte Basin has been completed, the results of which are being presented at this APPEA conference. Large seismic and well data sets, submitted under the Offshore Petroleum and Greenhouse Gas Storage Act 2006 (OPGSSA) are made available through the National Offshore Petroleum Information Management System (NOPIMS). Additional data and petroleum related information can be accessed through Geoscience Australia’s data repository. Appeared in The APPEA Journal 61(2) 294-324, 2 July 2021

The northern Lawn Hill Platform (nLHP) is considered an emerging region with less than 15 wells drilled to date. With renewed interest in unconventional gas, new exploration opportunities exist in this early Proterozoic region. Petroleum systems analysis is presented here to improve the understanding of burial history, source rock richness and maturity of the nLHP of the Isa Superbasin, far NW Queensland. A pseudo-3D geological model was built and calibrated, in combination with 1-D burial and thermal history modelling of Desert Creek 1 and Egilabria 1. These were combined with source rock characteristics (e.g., Rock Eval and kerogen kinetics) which helped assess the hydrocarbon generation potential by source rock, allowing a broader assessment of petroleum prospectivity of the nLHP. The study focussed on two potential source rocks; the Lawn 4 Sequence and the River Supersequence. Maturity modelling of the Lawn 4 Sequence at Desert Creek 1 and Egilabria 1 predicted equivalent vitrinite reflectance (EqVR) of over 1.2% and 2%, respectively. The River Supersequence was modelled as overmature at both wells. Combining these results with the pseudo-3D model and source rock characteristics demonstrates that the highest maturities are encountered in the deepest depocentres to the east and gradually decrease in maturity to the west, indicating some potential for wet gas. Modelling results show generation of varying amounts of gas and oil from each potential source rock. Overall, due to the age of the sediments, maximum depth of burial and high paleotemperatures, the most likely hydrocarbon phase is gas from primary generation and supplemented by secondary gas from oil cracking. In spite of high maturities, encouraging gas shows from the Egilabria prospect support continued exploration interest in this region for unconventional hydrocarbons.

In 2014-15 Geoscience Australia acquired 3,300 km of deep 2D seismic data over the northern part of the Houtman Sub-basin (Perth Basin). Prior to this survey, this area had a very sparse coverage of 2D seismic data with 50-70 km line spacing in the north and an industry grid with 20 km line spacing in the south. Initial interpretation of the available data has shown that the structural style, major sequences, and potential source rocks in this area are similar to those in the southern Houtman and Abrolhos sub-basins. The major difference between these depocentres, however, is in the volume and distribution of volcanic and intrusive igneous rocks. The northern part of the Houtman Sub-basin is adjacent to the Wallaby Plateau Large Igneous Province (LIP). The Wallaby Plateau and the Wallaby Saddle, which borders the western flank of the Houtman Sub-basin, had active volcanism from the Valanginian to at least the end of the Barremian. Volcanic successions significantly reduce the quality of seismic imaging at depth, making it difficult to ascertain the underlying thickness, geometry and structure of the sedimentary basin. The new 2D seismic dataset across the northern Houtman Sub-basin provides an opportunity for improved mapping of the structure and stratigraphy of the pre-breakup succession, assessment of petroleum prospectivity, and examination of the role of volcanism in the thermal history of this frontier basin.

This report highlights results of petroleum systems analysis undertaken on the northern Lawn Hill Platform area of the Isa Superbasin, specifically focusing on burial and thermal history modelling. A second report will highlight the results of the source rock analysis and maturity modelling.

Following a request by the Premier of South Australia an inspection of the Leigh Creek Coalfield was made on December 5th to December 8th, 1941. My opinion was sought chiefly on the probability of there being a considerable tonnage of coal available which could be won by open cut mining, preferably from one section of the field, near Telford Siding.

The Cooper Basin is a late Carboniferous-Middle Triassic intracratonic basin in northeastern South Australia and southwestern Queensland. The basin is one of Australia's premier onshore hydrocarbon producing provinces and, by providing domestic gas for the East Coast Gas Market, is nationally significant. This study reviews the distribution, quality and maturity of source rocks across the Cooper Basin and forms part of Geoscience Australia's source rock program. All publicly-available total organic carbon (TOC) content and Rock-Eval pyrolysis data for the Cooper Basin were compiled into a single database, quality checked and compiled by well and formation to highlight the multiple viable source rock units throughout the Permian. The Toolachee and Patchawarra formations represent the principal source rocks in the basin. These comprise coals and carbonaceous shales deposited in fluvial deltaic and peat swamp environments and show good to very good oil and gas source potential. Additional source intervals include the gas prone lacustrine Roseneath and Murteree shales, as well as coals and carbonaceous shales of the Daralingie and Epsilon formations. Permian source rock distribution was investigated using lithofacies mapping combined with geochemistry data. Lithofacies maps published for South Australia were integrated with electrofacies data from Queensland to produce new, internally consistent, net source thickness maps for key intervals, including coals and carbonaceous shales of the Toolachee and Patchawarra formations, and the Roseneath and Murteree shales. Pyrolysis data that indicate the presence of an in-situ source rock with remaining hydrocarbon generation potential (i.e. TOC > 2% and S1+S2 > 3 mg hydrocarbons/g rock) were mapped by formation, demonstrating the broad extent of Permian source rocks across the basin. Toolachee and Patchawarra source rocks are present in most major depocentres, including the Windorah Trough and Ullenbury Depression in the northern part of the basin, where maximum coal thicknesses still reach more than 10 m. Source rocks within the Roseneath and Murteree shale are generally restricted to the southern Cooper Basin.